Electrolytic Cell

ABSTRACT

The invention relates to an electrolytic cell comprising a housing having a channel extending there through; an inlet allowing water to pass into the channel; an outlet allowing water to pass from the channel; and a series of electrodes located within the channel; wherein the channel is a spiral.

CROSS REFERENCE

The present application is a National Stage entry from PCT Patent Application No. PCT/AU2010/000931 filed on 22 Jul. 2010, which claims priority to Australian Application 2009903424 filed on 22 Jul. 2009 the contents of each one incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to an electrolytic cell. In particular, the invention relates to an electrolytic cell used in chlorination of salt water swimming pools, spas and the like bodies of water.

BACKGROUND OF THE INVENTION

The chlorination of pools is necessary to prevent the unwanted growth of bacteria in the water. Electrolytic chlorination has become a popular method of achieving bacteria free water. Electrolytic chlorination uses common salt which is added to the water located within the pool in combination with an electrolytic cell which is used to produce chlorine. This chlorine is released into the water thereby killing any unwanted bacteria and micro organisms. This process is cost effective, low maintenance and environmentally friendly.

When using an electrolytic cell to chlorinate pool water, a by-product of this process is the formation of hydrogen gas. Normally the hydrogen gas is transmitted with the water flowing through the electrolytic cell into the pool and dissipated into the atmosphere. However, if the pool pump ceases to operate, the electrolytic cell will continue to operate, producing hydrogen gas. Instead of the hydrogen gas flowing with the water into the pool and subsequently into the atmosphere, the hydrogen gas can continue to build up. In extreme circumstances, this can cause an explosion if the hydrogen gas is ignited.

U.S. Pat. No. 4,861,451 describes an electrolytic cell which is configured to reduce the likelihood of a hydrogen explosion in an electrolytic cell. The electrolytic cell is configured so that an inlet and an outlet of the cell are located below electrodes located within the body of the electrolytic cell. If hydrogen gas does accumulate within the electrolytic cell, the hydrogen gas becomes trapped within the electrolytic cell forcing the water below the electrodes. This stops electrolyses from occurring and hence, stops the production of hydrogen gas.

The electrolytic cell, shown in U.S. Pat. No. 4,861,451, is very effective in limiting the amount of hydrogen produced by the electrolytic cell. However, because of the design of the electrolytic cell, there are some inherent disadvantages. When the electrolytic cell is in a horizontal position, water must flow through four 90 degree changes of direction in order to provide a trap for the hydrogen in electrolytic cell. This detracts significantly from the hydraulic efficiency of a pool chlorination system by adding additional pressure, which is theoretically equivalent to adding six metres of pipe to the system. When the electrolytic cell is in a vertical position, a looped arrangement is required at the top of the pool chlorination system to again provide a trap for hydrogen gas. This again adds a substantial amount of additional piping. This additional piping and the changes of direction of the water flow generally require a larger pump in order to pump water effectively through the chlorination system, making the chlorination system more expensive. Further, pumping is generally more complex with the change in pipe direction.

OBJECT OF THE INVENTION

It is an object of the invention to overcome or alleviate one or more of the disclosures or provide the consumer with the useful or commercial choice.

SUMMARY OF THE INVENTION

In one form, although not necessary the only or broadest form, the invention relates to an electrolytic cell comprising:

a housing having a channel extending there through;

an inlet allowing water to pass into the channel;

an outlet allowing water to pass from the channel; and

a series of electrodes located within the channel;

wherein the channel is a spiral.

The housing is typically formed from a base and a cap. Normally the housing is made of plastic but can be made from other suitable materials. The housing may also include side covers to cover a join between the base and the cap.

The inlet and outlet are typically in alignment with each other. However, the inlet and outlet may be at other angles, such as 90 degrees with each other.

The electrodes are typically located in the channel closer to the outlet than the inlet. The electrodes may be formed from any suitable material, such as titanium. The electrodes may be supplied with a mono-polar or bi-polar charge.

The electrodes may be removable from the channel. The electrodes may be individually replaced. The electrodes may be mounted to a central member. The central member may form part of the channel. The central member may be removable.

The electrodes may form part of an electrode cartridge. The electrode cartridge may be removable from the housing. The cartridge may include the central member which is used to mount the electrodes. An inner bracket may be also be used to mount electrodes to the central member. An outer member may also be used in mounting the electrodes to the central member.

The electrodes may be flat or curved. One or more edges of the electrodes may be arcuate in shape.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described with reference to the accompanying figures in which:

FIG. 1 is a front view of an electrolytic cell according to an embodiment of the invention;

FIG. 2 is a rear view of the electrolytic cell as shown in FIG. 1;

FIG. 3 is a perspective view of an electrolytic cell as shown in FIG. 1;

FIG. 4 is an exploded perspective view of the electrolytic cell as shown in FIG. 1;

FIG. 5 is a perspective view of an electrode cartridge in accordance with the first embodiment of the invention;

FIG. 6 is a partial perspective view of the cartridge shown in FIG. 5;

FIG. 7 is a perspective view of part of the cartridge as shown in FIG. 5; and

FIG. 8 is an exploded perspective view of part of the cartridge as shown in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 to 4 show an electrolytic cell 10 used for chlorination of pool water. The electrolytic cell 10 includes a housing 20 and an electrode cartridge 30.

The housing 20 is made up of a base 40, a cap 50 and two side covers 60. The cap 50 is removably attached to the base 40 by a series of cap bolts 51 which extend around a periphery of the cap 50. Bolt holes 41 are located within the base 40 for location of the cap bolts 51 to attach the cap 50 to the base 40. A seal 70 is located between the cap 50 and the base 40 to ensure a join between the cap 50 and the base 40 is water tight.

The side covers 60 fit over the join between the cap 50 and the base 40 to cover the cap bolts 51. The side covers 60 have a series of male members 61 which fit into associated female receivers 42 located on the base 40 to hold the side covers 60 to the base 40. The front side cover 60 also includes a conductor housing cover 62 to cover a conductor box 52 located on the cap 50.

An inlet 80 is located at one end of the base 40 with an outlet 90 located on the other end of the base 40. Both the inlet 80 and the outlet 90 have associated pipe connectors 100 to enable the housing 20 to be connected to associated pipes (not shown). The inlet 80 and outlet 90 are in alignment with each other. However, it should be appreciated that this may not necessarily be the case depending on the design of a pool chlorination system.

The electrode cartridge 30, shown in more detail in FIGS. 5 to 9, includes a removable central member 110, inner bracket 120, outer bracket 130 and a series of electrodes 140. The removable central member 110 is made of plastic and is shaped so that it fits into the housing 20, extending both into the base 40 and into the cap 50. The sides 111 of the removable central member 110 are shaped so that the sides 111 abut against the cap 50 and the base 40.

The outer bracket 130 and inner bracket 120 are used to mount the series of electrodes 140. The inner bracket 120 is removably attached to the removable central member 110 using attachment members 121 located on an inner surface 122 of the inner bracket 120. An outer surface 123 of the inner bracket 120 has a series of inner bracket recesses 125 which are used to mount the electrodes 140.

The outer bracket 130 also has a series of outer bracket recesses 131 located on the inner surface 132 of the outer bracket 130. A top 133 and bottom 134 of the outer bracket 130 have a series of apertures 135 located through the top 133 and bottom 134 of the outer bracket 130. This is to allow water to pass through the bracket 130 and over the electrodes 140. The outer bracket 130 is connected to the inner bracket 120 using an interference fit. The top 133 of the outer bracket 130 is shaped so that it fits snugly against an inner surface 132 of the cap 50.

Each electrode 140 in the series is a flat plate and has an arcuate outer edge 141 and inner edge 142. The electrodes 140 are shaped so that they will fit easily within the curved housing 20. It should be appreciated that the electrodes 140 may be sized, shaped and made from a variety of materials which would be evident to a person skilled in the art.

The electrodes 140 are electrically connected using two conductors 150 (i.e. cathodes or anodes) which pass through the cap 50 via the conductor box 52 and through associated holes in the electrodes 140. The conductors 150 are threaded at each end so that a conductor bolt 141 can be placed on either end of a conductor 150 to hold the series of electrodes 140 tightly against the inner bracket 120 and outer bracket 130. It should be appreciated that the connection of the electrodes 140 to the conductors 150 is well known in the art. It should also be appreciated that the current used may be varied. For example, the mono-polar or bi-polar current may be used.

When the removable central member is 110 located within the housing 20, a channel 160 in the shape of a spiral is formed. The spiral shaped channel 160 extends from the inlet 80, through the base 40, through the cap 50, back into the base 40 and out the outlet 90. It should be appreciated that the shape and size of the spiral shaped channel 160 may be varied depending on the particular requirement of the electrolytic cell 10 and associated plumbing of a pool's filtration system.

In use, water flows into the channel 160 through the inlet 80. The direction of water flow through the channel 160 is indicated by arrows 43 located on the base 40. The water then passes through the base 40 and into the cap 50 passing around an arcuate edge 112 of the removable central member 110. Water does not pass between the housing 20 and the sides 111 of the removable central member 110 due to the shape of the sides 111 of the removable central member 110 matching the housing 20.

Water then passes through the apertures 135 in the top 133 of the outer bracket 130. As the top 133 of the outer bracket 130 abuts against the inner surface of the cap 50, water must pass through the apertures 135 of the top 133 of the outer bracket 130. This reduces the area that the water can flow through. Accordingly, the velocity of the water is increased as it passes through the apertures 135 in the top 133 of the outer bracket 130, passes past the electrodes 140 and out through the apertures 135 in the bottom 134 of the outer bracket 130. This increase in velocity of the water may potentially reduce the build up of calcium on the electrodes 140. The water then passes through the base 40 and out of the outlet 90.

In use, the electrolytic cell 10 may be used in both a horizontal and vertical position. In the event of a pump failure, any excess hydrogen gas build up will be trapped within the cap 50. Any further build up will cause the water level to ultimately drop below the electrodes 140 stopping the production of dangerous hydrogen.

The spiral shape of the channel 160 allows the inlet 80 and outlet 90 to be in alignment. This increases hydraulic efficiency as the water does not need to pass through any 90 degree turns. Instead, the water moves from the inlet 80 to the outlet 90 via the spiral shaped channel 160 which has increased hydraulic efficiency compared to traditional electrolytic cells 10, as shown in U.S. Pat. No. 4,861,451.

It will also be appreciated that various other changes and modifications may be made to the embodiment described without departing from the spirit and scope of the invention. 

1. An electrolytic cell comprising: a housing having a channel extending there through; an inlet allowing water to pass into the channel; an outlet allowing water to pass from the channel; and a series of electrodes located within the channel; wherein the channel is a spiral.
 2. The electrolytic cell of claim 1 wherein the channel is a single loop spiral.
 3. The electrolytic cell of claim 2 wherein the housing is formed from a base and a cap.
 4. The electrolytic cell of claim 3 wherein the housing also includes side covers to cover a join between the base and the cap.
 5. The electrolytic cell of claim 1 wherein the inlet and outlet are in alignment with each other.
 6. The electrolytic cell of claim 1 wherein the electrodes are located in the channel closer to the outlet than the inlet.
 7. The electrolytic cell of claim 1 wherein the electrodes are supplied with a mono-polar or bi-polar charge.
 8. The electrolytic cell of claim 1 wherein the electrodes are removable from the channel.
 9. The electrolytic cell of claim 1 wherein the electrodes are individually replaceable.
 10. The electrolytic cell of claim 1 wherein the electrodes are mounted to a central member.
 11. The electrolytic cell of claim 10 wherein the central member forms part of the channel.
 12. The electrolytic cell of claim 10 wherein the central member is removable.
 13. The electrolytic cell of claim 1 wherein the electrodes form part of an electrode cartridge.
 14. The electrolytic cell of claim 13 wherein the electrode cartridge is removable from the housing.
 15. The electrolytic cell of claim 13 wherein the cartridge includes the central member which is used to mount the electrodes.
 16. The electrolytic cell of claim 15 wherein an inner bracket is used to mount electrodes to the central member.
 17. The electrolytic cell of claim 15 wherein an outer bracket is used in mounting the electrodes to the central member.
 18. The electrolytic cell of claim 1 wherein the electrodes may be flat or curved.
 19. The electrolytic cell of claim 1 wherein one or more edges of the electrodes are arcuate in shape. 